Grain-boundary structure and precipitation in sensitized austenitic stainless steel

Grain-boundary carbide precipitation and intergranular corrosion in sensiti zed austenite stainless steel were examined by transmission electron micros copy to clarify the effect of grain-boundary structure on precipitation and corrosion. The propensity to intergranular precipitation depends strongly on the grain-boundary structure. Carbide precipitates lend to be detected n t grain boundaries with higher Sigma values or larger deviation angles (Del ta theta) from low-Sigma coincidence site lattice misorientations. The more ordered boundary requires a longer time for intergranular carbide precipit ation and corrosion than less ordered or random boundaries.